on the streets of benghazi, libya, a different picture. hundreds of demonstrators rallied in support of america. they protested tuesday's attack on the u.s. consulate carried out by a rogue group of militants. four americans were killed, including the ambassador to libya, chris stevens, a rising diplomat, seen here in a youtube video. >> my name is chris stevens. and i'm the new u.s. ambassador to libya. >> he risked his life to stop a tyrant. then, gave his life to build a better libya. >> reporter: also killed, sean smith, an information specialist. >> as americans, we stand united, all of us, in gratitude for their service. i want to assure you, we will bring their killers to justice. >> reporter: a terror group affiliated with al qaeda has claimed responsibility for the well-coordinated attack in libya. officials believe it was timed coincide with the 9/11 anniversary and may not have been linked to the anti-muslim film that sparked the angry protests at the u.s. embassy in cairo and other cities. president obama said what could be a s